Manual three direction tracer



April 1963 A. DEVER ETAL 3,084,899

MANUAL THREE DIRECTION TRACER Filed Oct. 2 1, 1957 4 Sheets-Sheet l IN VEN TOR-S LEW/S A. DEVER BYCHARLES GSC'H WIND.

ATTORNE Y8 April 9, 1963 L. A. DEVER EIAL MANUAL THREE DIRECTION TRACER 4 Sheets-Sheet 3 Filed Oct. 21, 1957 h mmmmm M MIMMMIM I IN V EN TORS) LEW/6 A. DEVER BYOHflRLES L. GS'OH WIND. //6 WW Wr/MW ATTORNEYS.

April 9, 1963 Filed Oct. 21, 1957 IL. A. DEVER ETAL MANUAL THREE DIRECTION TRACER 4 Sheets-Sheet 4 IN V EN TORS LEW/5 A7. DEl/ER BY CHARLES L. GSOH W/ND HT TORNEYS 3,084,899 MANUAL TE DIRECTIQN TCER Lewis A. Dever and Charles L. Gschwind, Cincinnati, Ohio, assignors to The Cincinnati Miiling Machine (30., Cincinnati, Ohio, a corporation of Ohio Filed Oct. 21, 1957, Ser. No. 691,255 14 Claims. (Cl. 2513) This invention relates to pattern controlled machine tools and more particularly to tracer control mechanism therefor.

One of the objects of this invention is to provide a new and improved hydraulic tracer control mechanism having a deflectable tracer which may be manipulated to effect relative movement between a tool and work in two directions or three directions simultaneously.

Another object of this invention is to provide a new and improved construction of a tracer head, in which all the control valves are arranged parallel to the tracer spindle. Since, in normal operation, it is preferred that a tracer spindle be arranged in a vertical position, this means that the Weight of the valve members acts axially thereof rather than laterally, as prevalent in the prior art, thereby reducing friction in operation, and the valves have a chance to maintain a more central position in their sleeves, thus improving the hydraulic operation.

A further object of this invention is to provide a new and improved means for operating the tracer spindle from either end, so that the same direction of force applied to either operating means will produce a common resultant direction of operation of the controlled motors.

A further object of this invention is to provide a new and improved device of the character described in which the rates of movement in any of the directions may be conveniently controlled at one station both as to feeding rates and rapid traverse rates and that the rapid traverse rates can only be effected when the tracer is lifted from the pattern.

Another object of this invention is to provide a new and improved hydraulic tracer control mechanism having a deflectable tracer which may be manually controlled for following the contour of a pattern.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification, considered in conjunction with the accompanying drawings forming a part thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described, within the scope of the appended claims, without departing from or exceeding the spirit of the invention.

Referring to the drawings in which like reference numerals indicate like or similar parts:

FIGURE 1 is a view in elevation of the tracer control unit of this invention.

FIGURE 2 is a section on the line 2-2 of FIGURE 1.

FIGURE 3 is a section on the line 3-3 of FIGURE 1.

FIGURE 4 is a section on the line 4-4 of FIGURE 2.

' FIGURE 5 is a detail section on either of the lines 55 of FIGURE 4.

FIGURE 6 is a section on the line 66 of FIGURE 2.

FIGURE 7 is a detail view partly in sect-ion showing the feed-rapid traverse selector.

FIGURE 8 is a detail section on the line 8-8 of FIG- URE 7.

FIGURE 9 is a detail view on the line 99 of FIG- URE 7.

FIGURE 10 is a diagrammatic view showing the directions of control with respect to a work support.

Referring to the drawings, there is shown, in FIGURE 1, a view in elevation of an embodiment of this invention in which the reference numeral 10 indicates the lower housing, the reference numeral 11 indicates the upper housing and the reference numeral 12 indicates the cap structure, all of which make up the assembled structure of the tracer head of this invention. In the present invention the tracer mechanism is adapted to control relative movement in three directions between a tool and work support of a pattern controlled machine, and it is common practice in such machines that a separate prime mover be provided for effecting each of the directions of movement. This mechanism is devised to control the joint or several operation of these prime movers, and to this end there are provided three control valves, one for each direction of movement.

It is to be understood that it is preferable that this device be mounted on a machine and so oriented that the tracer finger 13, shown in FIGURE 1, has its three primary directions of movement arranged parallel to the movements of the three primary slides of the machine which eifect the relative movement between the tool and the work whereby the tracer finger is directional, and movement of it in a given direction will produce movement in that direction. For instance, if the machine has a slide, such as 14, shown in FIGURE 10 which may be considered, for example, as the work support which is guided lfOI' reversible movement in the direction of the arrow :15, the device of this invention is so mounted on a machine that the tracer 13 is deflectible in the plane of the arrow 15 so that deflection of the tracer in that plane will produce movement in that plane. Likewise, deflection of the tracer at right angles to this plane in the direction of the arrow 16 will produce movement only in the plane of the arrow 16. The tracer 13 is also subject to axial movement in the direction indicated by the arrow 1-7 which is at right angles to the plane containing the arrows 15 and 16 so that axial movement of the tracer will produce movement perpendicular to the table.

As shown in FIGURE 6, the control valves indicated generally by the reference numerals 18 and 19 control the movements in the directions '15 and 16 respectively, while the vertical control valve indicated generally by the reference numeral 20 controls the movement in the direction 17 perpendicular to the plane of movements 15 and 16. The tracer spindle 21, shown in FIGURES 2 and 4, is connected to an actuator plate 22 which, in turn, is operatively connected to the valves 18 and 19 in such a manner that tilting of the tracer finger 13 in one plane will operate the valve '18 without disturbing the valve 19, or it is defiectible in a second plane whereby it will operate the valve 19 without disturbing the valve 18. Similarly, axial movement of the tracer spindle 21 will effect actuation of the vertical control valve 20 without disturbing the valves 18 and 19.

Each of the horizontal control valves 18 and 19 are of the same construction, and as shown in FIGURE 2, the control valve 18 comprises a valve plunger 23 which is slidably mounted in a bushing 24. Each of the bushings 24, as shown in FIGURE 6, is spring urged axially by a flat spring member 25 which has a turned edge 26 that bears against the flat surface 27 of the upper housing 11, and also turned edges 28 and 29 which bear against the sleeves 24. A clamping screw 30 and washer 31 are threaded in the surface 27 to exert pressure of the spring member 25 on the ends of the bushings.

As shown in FIGURE 5, each bushing bears against an adjustable rod 32 which is slidable in a fixed sleeve 33 which has an adjustable set screw 34 threaded in the end thereof and provided with a lock nut 35. The object of this arrangement is that the sleeve may be adjusted relative to the ports in the valve plunger. Each sleeve 24 has a central annular groove 36 in which is formed ports 37 and which serves as a pressure supply groove. There are also terminal grooves 38 and 39 of similar construcaosasss tion which are connected by interdrilling to a reservoir line. Between the central groove and the terminal grooves are two motor supply grooves as and 41. The valve plunger 23 is slidable in the bushing and is pro vided with a central groove 42 and end grooves 43 and 44 which provide annular lands 45 and 46- which control the connection of the pressure groove 36 to the motor grooves 49 and 41.

The valve plunger 23 has a central bore 47 in which is slidably mounted a spherical ended plunger 48 for engagement with the actuator plate 22. The lower end of the valve plunger is provided with a lateral slot 4? in one side of which is mounted a ball d which bears against the underside of the plate 22. A strong spring 51 bears against the plunger 48 to securely clamp the valve plunger to the plate 22 by substantially point contact whereby tilting of the plate 22 to move the plunger axially will not XTL a side thrust on the valve plunger and cause it to bind in its bore. The spring 51 is backed up by a rod 52 and suitable set screws 53 mounted in the bore 47 of the plunger. It will now be seen that due to the nature of the construction by which the valve is clamped to the actuator plate 22, that there is no means for adjusting the axial position of the valve plunger to align the valve spools with the ports in a neutral position, and therefore the adjustment is made in the bushings as just described.

It will now be seen that the valve plungers of valve 18 and 19 are connected to the actuator plate 22, and these valves are spaced 90 degrees apart on a circumference about the center of the tracer spindle 21, and therefore the plate 22. may be considered as having two right angular related legs or levers connected to the plungers so that either plunger may be actuated without causing actuation of the other.

The actuator plate 22 has a spherical bearing surface 54 which rides on a spherical seat 55 formed in a supporting plate 56 which is secured to the top of opening 57 formed in the lower housing it by screws 5'3. The plate has an integral elongated sleeve 59 which is externally threaded on its lower end at 69 to which is attached a feed rate dial 61. The feed rate dial has a conical surface 62, formed on the upper side thereof which bears against a feed-rapid traverse selector sleeve 63 which is slidably mounted in the bore 57. This sleeve has an annular groove 64 in which is titted an eccentric pin 65, shown more particularly in FIGURE 7, and integrally formed on the end of a rod 65 mounted in a bore 67 formed in the lower housing 1%. The member 66 has an operating knob 68 integrally attached thereto. Locking screws 66, FIGURE 9, having a reduced end 67' fitting groove 68' in rod 66' hold the rod in place. A spring pressed detent ball 69', shown in FIGURE 8, serves to hold the rod in either one of its two positions.

A spring 6h is interposed between the members 61 and 63 which functions to hold the bearing surfaces 54 and S5 of the plate 22 in engagement. The sleeve 59 has an internal bore 70 in which is mounted an anti-friction sleeve 7i which acts as a retainer for the anti-friction balls 72 that form a close fit between the bore 7% and the cylindrical surface 73 of the tracer spindle 21. The anti-friction sleeve 71 is of sufiicient length that lateral movement of the tracer spindle will effect lateral movement of the sleeve 59 and thereby deflection of the actuator plate 22. This anti-friction means also permits free axial movement of the tracer spindle 21 with respect to the sleeve, and this movement is limited in a downward direction by a vertical feed rate dial 74 which is threaded internally in the lower end of the sleeve 5d and is provided with a shoulder 75' which engages a shoulder 76 formed on the periphery of the tracer spindle 21.

The tracer spindlehas formed midway of the length thereof an annular rib 77 which provides a conical hearing surface 78 on which the lower end of the vertical control valve plunger '79 seats. The valve plunger 79 is held against this seat by a spring 80 which surrounds the tracer spindle 21, and engages a shoulder 81 formed on the upper end of the valve plunger 79. The spring is interposed between this shoulder and a plate 8.2 which is secured to the upper end of the valve bushing 83 by suitable means such as the screws 84. The bushing 83 has a central pressure port 35 and exhaust ports 86 and 87 at either end thereof. Between the pressure port and the exhaust ports are two motor ports 88 and 89 which are suitably connected by interdrilling to the hydraulic motor which controls the vertical movement. Any connection of these ports is controlled by the annular grooves 9d, 91 and 92 formed in the valve plunger.

With respect to the operation of this device, attention is first invited to the fact that in the drawings the parts are all shown in such a position that all the valves are in a neutral or stop position and therefore all of the slides controlled thereby are stationary. For ordinary profiling operations which are usually carried out in one plane, such as the horizontal plane, it would only be necessary to utilize the two valves 18 and 19' while the vertical valve would remain in its neutral position. In that case the dial 61 is rotated in such a direction as to provide clearance between the conical surface 62 and the member 63 which thus provides space to permit lateral deflection of the tracer spindle. The further this adjustment is made, the greater the distance that the tracer spindle can be deflected and thus the greater the rate of relative movement between the cutting tool and the work. It will be noted that this adjustment can be made without disturbing the vertical control valve.

If it is desirable to retract the tracer plunger upward at any time, the knob 68 is turned which shifts the sleeve 63 upward and immediately enlarges the space betwee the surface 62 and the member 63, which means that the slides could be immediately traversed at a rapid rate.

When the sleeve 63 is adjusted vertically it carries a self-centering washer 93 which engages a cross pin 94 which is mounted in the tracer spindle 21. This pin passes through an elongated hole 95 formed in the sleeve 71 and also an elongated hole 96 in the sleeve 59 to permit movement of the pin Without disturbing these parts. It will, therefore, be seen that upward movement of the sleeve 63 will cause the pin 94 to move the tracer spindle 21 upward, and thereby shift the vertical valve above its neutral position and raise the tracer out of en gagement with the pattern.

It is noted by this construction that for normal tracing operations in a horizontal plane that the rate of movement between tool and work be confined to a feed rate and that fast rapid traverse rates only be permitted when the tracer has been retracted from the pattern such as for positional movements.

When it is desired to trace in three directions simultaneously then both of the dials 61 and 74 are adjusted, and adjustment of the dial 74 downward Will permit movement of the vertical control valve downward below its central or stop position. The parts will move down until the tracer engages some form of pattern surface which will push the tracer back and cause retraction of the shoulder 76 from the shoulder on the vertical rate dial 74 until the valve is moved back to a stop position. The operator may then deflect the tracer manually to cause it to follow a horizontal profile while at the same time the end of the tracer finger is hearing on another profile surface which controls the movement in a vertical direction.

It will now be seen that the spring which holds the depth valve plunger against the shoulder on the tracer spindle also exerts a downward thrust to hold the tracer spindle against the end of the depth dial 74-, and since this dial is internally threaded in the sleeve 59 it acts to hold the bearing surface 54 of the sleeve against the supporting surface 55 in the plate 56.

Theoretically, the tracer spindle oscillates about a point 97 on its axis, and this point is also theoretically the center of curvature of the bearing surface 78 and 54, and

it will also be noted that the point 97 is approximately in the top plane of the plate 22 which actuates the valve plungers of valves 18 and 19 depending on the direction of deflection of the tracer spindle about this point.

The upper end of the tracer spindle is provided with two fixed washers 98 and 99 and a spring 100 is interposed between them. Ihe lower end of the spring engages a cup Washer 101 which bears against the washer 98, and the upper end of the spring engages a conical ended sleeve 102 which bears against the washer 99. When the rapid traverse control knob 68 shown in FIG- URE 7 is rotated to move the sleeve 63, shown in FIG- URE 2, upward to engage the pin 94 and thereby effect axial movement of the tracer spindle, the tapered bearing surface 103 on the end of the sleeve 102 is forced into engagement with the shoulder 104- of the cap member 105, thus compressing the spring 100 and establishing a downwardly acting force on the tracer spindle whereby when the control 68 is rotated in the opposite direction the parts will be caused to return to their normal position. It will be evident that the engagement of the conical shaped member 102 with the shoulder 104 will normally center the tracer member 21 and thereby stop the prime movers which are controlled by the valve member 23 of valves 18 and 19. However, since the member 102 is resiliently mounted on the tracer member 21, with spring 100, the tracer member 21 may be deflected by the operator to effect selected operation of the prime movers controlled by valves 18 and 19, for movement of the slides in the directions indicated by arrows and 16 of FIG. 10, even when the control mechanism shown in FIG. 7 is in the position to hold the tracer member elevated and the member 102 is engaged with the shoulder 104.

Means have been provided for establishing a fixed amount of bias on the tracer spindle for holding the spindle in a deflected position without the aid of the operator, and this is usually utilized when the tracer is following a straight line on the pattern. It also may be adjusted to change the bias in any given direction throughout 360' degrees. Mounted on the top of the cap 105 is a rotatable housing 106 which has a bearing surface 107 by which it is supported for rotation on the top surface 108 of the fixed cap 105. The cap has an annular groove 109 formed in its periphery, and the housing 106 has a clamping screw 110' threaded therein with its end riding in the groove 109 whereby the screw 110 serves to keep the member 106 from lifting andalso serves to hold the member 106 in any particular rotatable position.

The housing 106 carries a biasing plunger 11 which has a bifurcated end 112 in which is mounted a roller 113 rotatable on a bearing pin 114. A spring 115 surrounds the plunger 111 to effect inward movement of the plunger toward the tracer spindle. The plunger 111 extends through the housing 106 in which it is guided, and its exterior end is provided with a control knob 116 which is fastened to it by a set screw 117. A fixed pin 118 is mounted in the housing 106 to normally bear against the inner surface 119 of the control knob 116 and thereby hold it in an axially retracted position against the resistance of spring 115'. In this position on the parts the roller 113 is held out of engagement with the tracer spindlel When it is desired to apply a bias to the tracer spindle, the knob 116 is rotated 90 degrees which aligns a hole 120 in the knob 116 with the pin 118 whereby the spring 115 will effect axial movement of the plunger as the pin 118 enters the hole 120. This aligns the roller 113 in a horizontal plane against the cylindrical surface 121 on the tracer plunger. It will be obvious that this will deflect the tracer plunger in one given direction and in order to change that direction, the operator merely grasps the knob 11-6 and rotates the housing 106 about the cap member 105. Thus, the tracer spindle is automatically held in a deflected position to produce a given feed rate depending on the setting of the rate dial 61 and the operator merely steers or controls the direction of movement.

Attention is invited to the fact that when the operator utilizes the tracer finger 13 to control the direction of movement and especially three-directional movement where the tracer finger must dive into a cavity there may not be room in the cavity for the operator to conveniently grasp and control the tracer finger and therefore, for convenience, as well as safety to the operators hand, a second control has been provided on the top of this device whereby the operator may conveniently control the deflection of the tracer spindle as efliciently as he could by utilizing the tracer finger. This control is mounted in the upper housing indicated generally by the reference numeral 12 and a tubular sleeve 121 as shown in FIGURE 3 which has an annular shoulder 122 on the end thereof which fits into a bore 123 formed in the end of the housing 106. This sleeve has an annular ring 124 fixed in the wall of the internal bore 125 of the sleeve which supports a sliding sleeve 126. The sleeve 126 has a shoulder 127 formed thereon which is engaged by a spring 128 which has its other end engaging a cap 129 mounted on the end of the member 121' and secured thereto by conventional means such as the screws 130. The member 126 has a central bore 131 in which is fitted the ball-shaped portion 132 of the auxiliary control lever 133. The lower end of this lever has a bearing sleeve 133 secured thereto for receiving the ball-shaped end 134 of a screw 135 threaded in the end of the tracer spindle 21. Suitable washers 136 are secured in the end of the member 133' to hold the portion 134 in the end of the sleeve.

The upper end of the control lever 133 is provided with a manual operating knob 137 and a spring 138 interposed between a fixed washer 139 on the member 126, and a washer 140 carried by the lever 133 acts to hold the lever 137 in a raised position and also to take out any lost motion between the ball 134 and its bearing washer 136. It will be seen that the lever 133 may be deflected in any direction by the operator grasping the control knob 137 and swiveled about the portion 132 as well as being moved axially against the resistance of spring 138. It will also be noted that the direction of push on the knob 137 is the same direction as the push on the tracer finger 13 for a desired direction of movement.

What is claimed is:

1. In a tracer mechanism having a housing containing control valve means for governing operation of individual prime movers, the combination of an elongated tracer member, means supporting said member in the housing for axial movement and lateral deflective movement, said valve means including a first valve operatively connected for response to axial movement of the tracer member, additional valve members supported in said housing in radial spaced relation to said tracer member and axially parallel thereto, and means extending laterally from said tracer member and operatively connected to said last-named valve members to effect joint or several operation thereof in response to said lateral deflective movement of said tracer member.

2. In a tracer mechanism comprising a housing having control valve means therein for governing operation of several prime movers, the combination of an elongated tracer member, means supporting said member in the housing for axial movement and lateral deflective movement, a first valve member supported in telescoping relation to said tracer member, additional valve members supported in spaced circumferential relation about said tracer member for axial movement parallel to said member, means operatively connecting said tracer member to said telescoping valve member for response to axial movement thereof, and means responsive to lateral movement of the tracer member to effect joint or several operation of said circumferentially spaced valve members.

3. In a tracer mechanism comprising a housing having control valve means therein for governing operation of assesses several prime movers, the combination of an elongated tracer member, means supporting said member in the housing for axial movement and lateral deflective movement about a point intermediate the length of said tracer member, a first valve operatively connected for response to axial movement of the tracer member, a pair of valve members supported in spaced circumferential relation about said tracer member and spaced at an angle of 90 degrees, means supporting said valve members for axial movement substantially parallel to the axis of said member to effect joint or several operation thereof in response to lateral deflective movement of the tracer member including a plate actuator extending laterally from said tracer member, and bifurcated means on said valve members gripping the edge of said plate.

4. In a tracer mechanism comprising a housing having control valve means therein for governing operation of several prime movers, the combination of an elongated tracer member, means supporting said member in the housing for axial movement and lateral deflective movement about a point intermediate the length of said tracer member, a first valve operatively connected for response to axial movement of the tracer member, a pair of valve members supported in spaced circumferential relation about said tracer member and spaced at an angle of 90 degrees, means supporting said valve members for axial movement substantially parallel to the axis of said member to effect joint or several operation thereof in response to lateral deflective movement of the tracer member including a plate actuator extending laterally from said tracer member, and bifurcated means on said valve members gripping the edge of said plate, said bifurcated means including a solid shoulder engaging one side of said plate and a resilient shoulder engaging the other side of said plate.

5. In a tracer mechanism comprising a housing having control valve means therein for governing operation of several prime movers, the combination of an elongated tracer member, means supporting said member in the housing for axial movement and lateral deflective movement about a point intermediate the length of said tracer member, a first valve operatively connected for response to axial movement of the tracer member, a pair of valve members supported in spaced circumferential relation about said tracer member and spaced at an angle of 90 degrees, means supporting said valve members for axial movement substantially parallel to the axis of said member to effect joint or several operation thereof in response to lateral deflective movement of the tracer member including a plate actuator extending laterally from said tracer member, bifurcated means on said valve members gripping the edge of said plate, said bifurcated means including a solid shoulder engaging one side of said plate and a resilient shoulder engaging the other side of said plate, and means to adjust the pressure of said resilient shoulder.

6. In a tracer mechanism comprising a housing having control valve means therein for governing operation of several prime movers, the combination of an elongated tracer member, means supporting said tracer member at a point intermediate its ends in said housing for axial and pivotal movement, a first 'valve operatively connected for response to axial movement of the tracer member, valve members arranged in circumferential relation about said tracer member with their axes substantially parallel to the tracer member, means operatively connecting said valve members to the tracer member for imparting axial movement to said valve members in response to pivotal movement of said tracer member, valve bushings mounted in said housing in telescoping relation to said valve members, and means in said housing for axially adjusting said bushings relative to said valve members.

7. In a tracer mechanism comprising a housing having control Valve means ere n for governing operation of several prime movers, the combination of elongated tracer member, means pivotally supporting the tracer member intermediate its length in the housing, motion transmitting connections from said tracer member to said valve means, a pattern engaging tracer finger detachably connected to one end of said tracer member for manual deflection thereof about its pivot, a manual control lever pivotally mounted on the housing on the other side of said pivot from said tracer finger and in substantially axial alignment With said tracer member, and means operatively connecting said control lever to the end of said tracer member for alternative manual operation thereof.

8. In a tracer mechanism comprising a housing having control valve means therein for governing operation of several prime movers, the combination of an elongated tracer member, means pivotally supporting the tracer member at a point intermediate the length thereof in said housing for pivotal movement, a valve actuator plate extending laterally from said member into operative en gagement with said valve means, said actuator plate having an integral sleeve surrounding said tracer member, a rate control bushing threaded on the end of said sleeve and having a tapered surface, a cooperating bushing having a fixed position in the housing, said last-named bushing having an internal conical surface in spaced relation to said tapered surface, means for adjusting said firstnamed bushing toward and from said conical surface to vary the rate produced by deflection of the tracer member of said valve means, independent means for moving said cooperative bushing from its first fixed position in said housing to a second fixed position to allow additional deflection of said tracer member to effect rapid traverse movements, an additional control valve telescoping said tracer member, and additional motion transmitting means connecting said independent means for simultaneously positioning said control valve in a rapid traverse position upon actuation thereof.

9. In a tracer mechanism comprising a housing having control valve means therein for causing operation of several prime movers, the combination of an elongated tracer member, means pivotally supporting the tracer member in said housing about a point intermediate the length thereof, a laterally extending plate actuator having operative connections to some of said valve means, said plate actuator having a sleeve anti-frictionally received on said tracer member, an additional control valve member telescopingly mounted on said tracer member, means supporting said last-named valve member on the tracer member whereby axial movement of said tracer member will effect operation of the valve, said sleeve having means externally threaded thereon for adjustment tolimit the lateral movement of said tracer member, and additional means internally threaded in said sleeve for limiting the axial movement of said tracer member.

10. In a tracer mechanism having a housing, the combination of an elongated tracer member having one end extending below the housing and adapted to engage a pattern, means supporting the tracer member in the housing for axial movement and lateral deflective movement, valve members Within the housing for governing operation of individual prime movers, one of said valve members encircling the tracer member in spaced relation thereto, means operatively connecting said :one valve member to the tracer member for movement in response to axial movement thereof, means operatively connecting said other valve members to the tracer member for movement in response to lateral deflective movement thereof,

a manual control lever pivotally mounted on top of the housing in substantially axial alignment with said tracer member, and means pivotally connecting one end of said control lever to the other end :of the tracer member.

11. A tracer mechanism having a housing, an elongated tracer member supported in the housing for axial movement and lateral deflective movement about a pivot point, a first valve member operatively connected to the tracer member for response to axial movement thereof, additional valve members supported in spaced circumferential relation about said tracer member and operatively connected thereto for response to lateral deflective movement thereof, said additional valve members being in a predetermined condition when said tracer member is centered, a manually operated control mechanism operable selectively to shift said tracer member axially a predetermined amount and operate said first valve member, said mechanism having means to hold the tracer member in its shifted axial position, a conical shaped member resiliently mounted on the tracer member spaced from said pivot point, and means fixed relative to the housing and positioned to engage said conical shaped member on shifting of the tracer member said predetermined amount to center the tracer member, whereby said additional valve members normally assume their predetermined condition when the tracer member is axially shifted and said tracer member may be manually deflected from its centered position when in its shifted axial position selectively to alter the condition of said additional valve members.

12. A tracer mechanism having a housing, an elongated tracer member supported in the housing for axial movement and lateral deflective movement about a pivot point, a first valve member coaxial with the tracer member and operatively connected thereto for axial movement therewith, a pair of additional valve members supported 90 degrees apart in spaced circumferential relation about said tracer member for axial movement parallel to the tracer member, means extending laterally from the tracer member and operatively connected to said pair of additional valve members to elfect joint or several operation thereof in response to lateral defiective movement of the tracer member, said additional valve members being unoperated when the tracer member is centered, a manually operated control mechanism operable selectively to shift the tracer member axially a predetermined amount and operate said first valve member, said mechanism having means to hold the tracer member in its shifted axial position, a conical shaped member resiliently mounted on the tracer member spaced from said pivot point, and a shoulder supported in fixed relation to the housing at a position to engage said conical shaped member on shifting of the tracer member said predetermined amount to center the tracer member, whereby said additional valve members normally are unoperated when the tracer member is axially shifted and said tracer member may be manually deflected from its centered position when in its shifted axial position selectively to operate said additional valve members.

13. A master control valve assembly for use in a threedimensional follower system, said valve assembly comprising a stationary support having a socket, rigid arm means universally supported in said socket, a stylus extending through the center of said socket normal to the plane of said arm means, said stylus being freely slidable axially thereof relative to said socket, three fixedly-supported hydraulic flow control valves enclosing movable valve elements, one of said valve elements being aligned with and in contact with one end of the stylus, the movable valve elements of the other two valves being operatively connected with respective ones of said arm means at points spaced degrees apart in a plane at right angles to the axis of said stylus and intersecting said socket, said valve elements being responsive to the slightest movement of the free end of the stylus in any direction to move one or more of said movable valve elements to modify fluid flow therethrough.

14. A master control valve assembly for use in a threedimensional follower system, said valve assembly comprising a stationary support having a socket, rigid arm means universally supported in said socket, a stylus extending through the center of said socket normal to the plane of said arm means, said stylus being freely slidable axially thereof relative to said socket, three fixedly-supported hydraulic flow control valves enclosing movable valve elements, one of said valve elements being aligned with and in contact with one end of the stylus, the movable valve elements of the other two valves being operatively connected with respective ones of said arm means at points spaced 90 degrees apart in a plane at right angles to the axis of said stylus and intersecting said socket, said valve elements being responsive to the slightest movement of the free end of the stylus in any direction to move one or more of said movable valve elements to modify fiuid flow therethrough, the center of said socket and the operative connections between said arms and the valve elements actuated thereby lie in substantially a common plane in all operating positions of said control valve assembly.

References Cited in the file of this patent UNITED STATES PATENTS 2,239,625 Roehm Apr. 22, 1941 2,332,532 Roehm Oct. 26, 1943 2,403,519 Gardiner July 9, 1916 2,424,031 Heer July 15, 19 47 2,433,005 Turchan Dec. 23, 1947 2,494,228 Cederholm Jan. 10, 1950 2,618,244 Roehm Nov. 18, 1952 2,723,827 Humes Nov. 15, 1955 2,787,437 Turchan Apr. 2, 1957 2,788,718 Martellotti Apr. 16, 1957 2,835,466 Rosebrook May 20, 1958 FOREIGN PATENTS 757,589 Great Britain of 1956 

1. IN A TRACER MECHANISM HAVING A HOUSING CONTAINING CONTROL VALVE MEANS FOR GOVERNING OPERATION OF INDIVIDUAL PRIME MOVERS, THE COMBINATION OF AN ELONGATED TRACER MEMBER, MEANS SUPPORTING SAID MEMBER IN THE HOUSING FOR AXIAL MOVEMENT AND LATERAL DEFLECTIVE MOVEMENT, SAID VALVE MEANS INCLUDING A FIRST VALVE OPERATIVELY CONNECTED FOR RESPONSE TO AXIAL MOVEMENT OF THE TRACER MEMBER, ADDITIONAL VALVE MEMBERS SUPPORTED IN SAID HOUSING IN RADIAL SPACED RELATION TO SAID TRACER MEMBER AND AXIALLY PARALLEL THERETO, AND MEANS EXTENDING LATERALLY FROM SAID TRACER MEMBER AND OPERATIVELY CONNECTED TO SAID LAST-NAMED VALVE MEMBERS TO EFFECT JOINT OR SEVERAL OPERATION THEREOF IN RESPONSE TO SAID LATERAL DEFLECTIVE MOVEMENT OF SAID TRACER MEMBER. 